Want to know how to setup your Chromecast HDMI dongle?

Couldn't find a graphic anywhere on the google site telling me how to setup a Chromecast dongle? I was wondering if it was a USB or a HDMI device. I had to set up the Chromecast app to get this image. Now I know. It's an HDMI device just like I suspected. :)

Which world cup team are you?